diff options
Diffstat (limited to 'drivers/dma/sh/shdma-of.c')
-rw-r--r-- | drivers/dma/sh/shdma-of.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/dma/sh/shdma-of.c b/drivers/dma/sh/shdma-of.c new file mode 100644 index 0000000..11bcb05 --- /dev/null +++ b/drivers/dma/sh/shdma-of.c @@ -0,0 +1,82 @@ +/* + * SHDMA Device Tree glue + * + * Copyright (C) 2013 Renesas Electronics Inc. + * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * + * This is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ + +#include <linux/dmaengine.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/shdma-base.h> + +#define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan) + +static struct dma_chan *shdma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + u32 id = dma_spec->args[0]; + dma_cap_mask_t mask; + struct dma_chan *chan; + + if (dma_spec->args_count != 1) + return NULL; + + dma_cap_zero(mask); + /* Only slave DMA channels can be allocated via DT */ + dma_cap_set(DMA_SLAVE, mask); + + chan = dma_request_channel(mask, shdma_chan_filter, (void *)id); + if (chan) + to_shdma_chan(chan)->hw_req = id; + + return chan; +} + +static int shdma_of_probe(struct platform_device *pdev) +{ + const struct of_dev_auxdata *lookup = pdev->dev.platform_data; + int ret; + + if (!lookup) + return -EINVAL; + + ret = of_dma_controller_register(pdev->dev.of_node, + shdma_of_xlate, pdev); + if (ret < 0) + return ret; + + ret = of_platform_populate(pdev->dev.of_node, NULL, lookup, &pdev->dev); + if (ret < 0) + of_dma_controller_free(pdev->dev.of_node); + + return ret; +} + +static const struct of_device_id shdma_of_match[] = { + { .compatible = "renesas,shdma-mux", }, + { } +}; +MODULE_DEVICE_TABLE(of, sh_dmae_of_match); + +static struct platform_driver shdma_of = { + .driver = { + .owner = THIS_MODULE, + .name = "shdma-of", + .of_match_table = shdma_of_match, + }, + .probe = shdma_of_probe, +}; + +module_platform_driver(shdma_of); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("SH-DMA driver DT glue"); +MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); |